JP4931253B2 - Method of manufacturing laser diode having coaxial line structure and light emitting device thereof - Google Patents

Description

The present invention relates to a manufacturing method of a laser diode having a coaxial line structure and an issuing light device thereof.

The solid-state semiconductor light source is an important product for saving optical communication, industrial observation, and white light illumination because it is highly efficient and can be used conveniently for its small volume. The light emitted from the conventional light emitting diode is due to spontaneous emission produced by recombination of electrons and holes. The phase, polarization, and radiation direction do not coincide with each other, and the light is randomly produced as shown in FIG. 1A and is called incoherent light (Incoherent Light). Using a cavity resonator (cavity resonator) for semiconductor laser light, spontaneously generated light waves produce standing wave oscillation between the lens surfaces of both ends of the cavity resonator and form stimulated emission (stimulated emission) FIG. 1B shows that the laser action principle of Optical Amplification is repeated, and the coherent light (Coherent Light) having the same phase, polarization, and radiation direction is excited and emitted in this way. It is. FIG. 2 shows that a light-emitting diode with a different configuration produces a Fabry-Perot laser, 200 represents a raw voltage supply electrode, 201 represents a p-type AlGaAs semiconductor, 202 represents an n-type AlGaAs semiconductor, Reference numeral 202 designates an active layer p-type GaAs semiconductor limiting layer (Confinement Layer) or covering layer (Cladding Layer) 206 from above and below, and its purpose is to limit the carriers in the active layer to emit light. 203 represents an n ⁺ type GaAs substrate, 204 represents a p ⁺ type GaAs substrate, and 205 represents a negative voltage supply electrode. Since the directions of the light rays after the laser action expands coincide, η _ex (Extraction Efficiency) becomes relatively high. Assuming that η _wp (Wall-Plug Efficiency) frequently used by light emitting diodes, the efficiency conversion efficiency of the light emitting diodes is the ratio of the light output efficiency and the input efficiency. Further, η _wp = η _int xη _ex x η _v , η _v is voltage efficiency, and η _v = h υ / qV. And η _int internal quantum efficiency is the ratio of the number of photons and the number of electrons and holes combined, η _int = ( _led P _opt / hυ) / (I / q), where h is Planck's constant and υ is the photon frequency , Q is the charge, V is the voltage, I is the current, and _led P _opt is the light output efficiency of the light emitting diode. That is, η _wp = η _int xη _ex x η _v
= ( _led P _opt / hυ) / (I / q) x η _ex x (hυ / qV)
= ( _led P _opt x η _ex ) / IV (1)

Thus, in order to obtain a relatively high conversion efficiency η _wp at a constant output power IV, the internal quantum efficiency must be increased in order to obtain a high light output power _led P _opt and a higher light extraction efficiency η _ex .

FIG. 3 shows the relationship (PI characteristic) of the luminous efficiency of a solid semiconductor with respect to a known current. In the figure, the characteristics of the light emitting diode in the spontaneous emission region and the stimulated emission laser diode are compared. In a light emitting diode having a special configuration, like a DFB laser or a Fabry-Perot laser, when a positive current reaches a starting current, all of the injected current flows into the laser light and is emitted from the inside of the semiconductor. If the injection current unit in the spontaneous emission region is assumed to be 1 iu before the laser works, and the light emission output power supply is compared as 1 pu calculation, current is injected twice into 2 iu in the laser operation region, producing 16 pu output light And it can be seen from equation (2) that many 15 pu power supply units come out.
II _th = e UB (N _e -N _o ) N _p = (e U / τ _p ) N _p (2)
I represents the current flowing after the starting current, I _th represents the starting current, U represents the volume of the active working layer, B represents the probability that the stimulated emission produced by the injected electrons has disappeared, and e represents the amount of electronic charge the stands, N _p represents the minimum activation carriers (electrons) density. N _p represents stimulated emission photon density, τ _p represents photon average lifetime, and can be expressed by the following equation.
τ _p = (n / c) (α + L ^-1 ln R ^-1 ) ^-1 (3)
n represents the active working layer diffraction index, c represents the speed of light, α represents the absorption value of the active working layer material with respect to the light wave absorptance for each length, L represents the cavity length, and R represents both end faces. Represents the reflectance. Expression when the current exceeds a star current I _th (2), flowed electrons is directed to all stimulated emission, the emission power is indicated by the slope ratio of the stimulated emission zone of Figure 3, in direct proportion with (II _th) Become. Differentiating the equation (2), the following equation is obtained.
d N _p / d I = τ _p / e U (4)
This equation indicates that the current flowing through the laser diode produces a photon density of induced emission, and it can be seen that the average lifetime τ _p of the induced emission photon becomes longer and the gradient becomes larger. From the equation (3), it can be seen that the material absorption α of the active layer is small, the cavity length is long, the tilt rate is large, and a higher light output is produced.

The luminous efficiency of a laser diode includes four types of display formulas: η _i (Internal Efficiency), η _d (Differential Quantum Efficiency), η _t (Total Device Efficiency), and η _l (Laser Efficiency).

Definition of internal efficiency becomes percentage of the injected electron number N _e for stimulated emission photons number N _p of forward biased to produce, i.e. _{η i = (N p / N} e) x 100% (5)

The differential quantum efficiency is the percentage of the number of electrons injected per hour relative to the number of stimulated emission photons produced per hour, that is, η _d = (d ( _ld P _opt / hν)) / d (I / e)
= (d _ld P _opt / d I) / E _g (6)
E _g in the equation represents the minimum band gap (E _g = E _c −E _v ) of the emission wavelength of the employed light emitting material, and _ld P _opt represents the luminous efficiency of the laser diode as shown in FIG. The inclination rate is given by the following equation.
tanα = d _ld P _opt / d I = η _d x E _g (7)

The definition of the total element efficiency is the ratio of the number of photons emitted outward and the number of injected electrons, and is expressed by the following equation (8).
η _t = ( _ld P _opt / h υ) / (I / e)
= _ld P _opt / IE _g
= η _d (1- (I _th / I)) (8)

The definition of laser efficiency is the ratio of output optical power to input power, that is, η _l = _ld P _opt / IV = η _t x (E _g / V) (9)
V represents that the voltage of the laser diode is applied, and the display formula of the laser efficiency and the power supply efficiency of the light emitting diode is the same. Light-emitting diode power conversion efficiency η _wp (η _wp = ( _led P _opt x η _ex ) / IV) and laser diode laser efficiency η _l (η _l = _ld P _opt / IV) are the optical output power and input power However, when comparing the slope ratio, the laser diode is significantly higher than the slope ratio of the light emitting diode. The main difference is that the extraction efficiency η _ex of spontaneous diffusion emission is relatively low, and stimulated emission is increased current (I-I _th ) (re-injection) above the star current I _th compared to the cavity resonator current All the carriers) will flow to stimulated emission, and the slope will be greatly increased. Further, it can be seen from the formula (2) that the purpose of the output power source is increased by increasing U, that is, the volume of the active layer and further injecting electrons. For the purpose of maximizing optical energy or power savings, the only choice is to oscillate using a cavity resonator standing wave to obtain a highly efficient extraction laser action and a light emitting structure with an active layer emission volume. However, currently there is a drawback when using the highest power efficiency laser light as the lighting function of lightning high-efficiency conversion, the disadvantages are as follows,
First, the light spot concentration cannot achieve the purpose of illuminating a large area, and further, the energy is concentrated to produce a destructive force that causes the object to be burned without being able to burn the retina or being uncontrollable.
Second, known laser crystal particles are generated by splitting from conventional semiconductor wafer epitaxy, and the laser crystal particles have an active working layer that emits light, the volume of which is limited to a predetermined level, and limited spontaneous emission. With the initial light energy, it has a lightning high-efficiency conversion of laser expansion action, and even if it is demonstrated, expansion is limited. Laser crystal particle cutting methods that include expensive volume circuit equipment processes and expensive wafer planar precipitation or epitaxy processes are costly to manufacture and, of course, are offered in large quantities that the masses can use. I can't do it.

  If the above drawbacks are solved one by one, a solid-state laser can be realized with high efficiency for the purpose of illumination. At the same time, the external quantum efficiency with low spontaneous emission that occurs in conventional solid state lighting devices of white light emitting diodes can solve various problems caused by the production of internal heat absorption loss. The effect of true white light illumination using.

  Lighting is essential in buildings, day and night, and it is required to be able to act and work safely. Conventional power lighting devices consume resources on the earth day and night, and improvement is essential. As described above, when the conventional white light diode manufactured by the previous technology is provided for illumination, due to the disadvantage of relatively low extraction efficiency, absorption loss generates heat due to the overlap of diffused light emission and unextracted photons, etc., and it is used for a long time Not suitable for lighting saving purposes. Even if a laser with high extraction efficiency is improved and used for lighting applications, it cannot be popularized at a high cost, and it has a disadvantage that it has a laser beam with high output isotropy and cannot disperse white light uniformly. .

The present invention utilizes the patent name “Diffraction Index Distribution in a Coaxial Light Guide System Shared with a Radial Coaxial Light Guide Fiber and its Coaxial Semiconductor Light Source and Detector” of its own claim “Taiwan Patent Number: 095146963”. The structural principle of the semiconductor light source and the principle of the coaxial light guide fiber invent and extend the linear linear laser diode and the coaxial light emitting fiber to solve the above problems. Details are as follows:
1. Coaxial semiconductor light source structure is completed by extending the coaxial laser crystal bar, and a laser diode having a coaxial line structure is completed by dividing it, and if both sides are cut, material can be easily saved and cost can be reduced. be able to. A coaxial semiconductor light source is a coaxial semiconductor light source that supplies power in a coaxial manner, including a coaxial light emitting diode and a coaxial laser diode. . FIG. 4 shows an example of a coaxial semiconductor laser structure of a communication wavelength light source. A feedback type heterojunction semiconductor laser in which concentric unions of coaxial annular semiconductor layers are distributed (Coaxial DFB Heterojunction Laser). ) Shows a local cross-sectional view of the structure, which is a coaxial laser that modifies and innovates a DFB heterojunction laser having a conventional flat structure. This example represents the production of a coaxial laser diode on a wafer substrate. This coaxial semiconductor laser is composed of various semiconductor materials such as homojunction (Homojunction), isotype heterogeneous junction (Heterojunction), or nonisotopic (Uniisotype) heterojunction. Spontaneous light emission acts as a stimulated emission laser. These laser emission actions are distributed feedback laser diode (DFB) or distributed Bragg reflector (Distributed Bragg) so that the conventional technology adopts the feedback action of Bragg's grating. Create a Reflector Laser Diode (DBR) laser.

The coaxial semiconductor laser light source of this example will be described by taking a coaxial distributed feedback heterogeneous junction laser diode DFB, which is one of the above. The coaxial distributed feedback heterogeneous semiconductor laser structure includes a conductor axial center electrode 407 that provides an anode and a coaxial outer ring feed electrode 408 conductor that provides a cathode, and a multi-layered annular concentric semiconductor layer therebetween is installed together, and an n-type InP substrate Completed in 409. 404 represents an annular active action layer InGaAsP layer, 405 represents a p-type InGaAsP layer of an annular semiconductor layer, 406 represents a reflective layer, and 403 represents a Bragg distributed feedback layer diffraction grating. The diffraction grating 403 is formed of a 401n-type annular InP semiconductor layer and a 402n-type InGaAsP annular semiconductor layer, and the feedback wavelength λ _B of the Bragg diffraction grating can be obtained by the following equation.
λ _B = 2nΛ / m (10)
n represents the semiconductor material diffraction rate, Λ represents the length of the period of the Bragg diffraction grating, m represents the value of 1 or 2, and the diffraction ordinal number (Order of Diffraction, usually 1). First, the emission wavelength λB is determined, and manufacturing the Bragg diffraction grating in the conventional wafer substrate flat precipitation technique, that is, manufacturing the Bragg diffraction grating, consumes a large amount of cost in the process of repeating the period length λ (thickness). This surface emitting laser is manufactured by fabricating a Bragg diffraction grating with a 401n-type annular InP semiconductor layer, and then forming an internal Bragg diffraction grating 402n type InGaAsP annular semiconductor layer by precipitation or epitaxy again. To complete a Bragg distribution feedback laser DFB laser. This laser is a light source for optical communication, and its manufacturing cost is relatively high and its luminous efficiency is high, but it is not suitable for popularization as a cheap illumination light source for the masses. Also shown in FIG. 5 is a conventional vertical cavity surface emitting laser light source (also called Vertical Cavity Surface Emitting Laser, VCSEL or Resonant Cavity Light Emitting Diode Resonate Cavity Light-Emitting Diodes, RCLEDs). Represents a Bragg reflecting mirror, 502 represents a working layer, 503 represents a buffer layer, 505 represents a top Bragg reflecting mirror, and 506 represents an annular electrode. In the production of the DBR distributed Bragg reflector of this laser, the thickness is determined in each of the upper and lower DBR reflectors and is repeatedly precipitated. Therefore, the production rate of VCSEL laser is low, the cost is high, and the Bragg reflector DBR diffraction grating distributed vertically is an ultra-thin sedimentation tank, and its epitaxial growth layers 501 and 505 are produced by the Bragg diffraction grating. The high λ / 4 curvature and low λ / 4 diffractive power when the device is forward biased in the material epitaxy layer, the voltage across these ultrathin layers drops. In particular, the discontinuous energy band of the heterogeneous joint surface prevents the flow of current.
The unstable current caused in this way is inconvenient for the power increase, and the VCSEL laser cannot output high power, so that the high power output laser is shown in the cross-sectional view of the DFB laser diode of FIG. Manufacturing face-to-face lasers.

  All of the edge-type lasers or surface-emitting lasers produced by the above flat precipitation are produced by precipitation with a conventional semiconductor wafer, and then finished by dividing into four sides and polishing. The surface-emitting type coaxial laser of the present invention is also an exception. is not. The wafer is completed by grinding and polishing both the upper and lower surfaces of a pure material crystal bar (Ingot) grown at a very slow speed. Such low-yield and expensive materials are currently being demanded in large quantities in semiconductor science and technology integrated circuits, photoelectric light-emitting lighting, and solar cell-making science and technology. It's not enough. It has already influenced the development of photoelectric science and technology, and indirectly hinders efforts to save people. If this laser product is obtained through a process of cutting and polishing the top, bottom, left, and right sides, it is unfortunate that the product is very rough.

In order to maintain the high quantum efficiency advantage of coaxial laser diodes and avoid high cost wafer deposition, it prevents loss due to material consumption of the six-sided cut. The present invention utilizes the “Taiwan Patent No. 096169661” and the patent name “Solid State Lighting Device Having Coaxial Line Type Light Emitting Diode Structure” claimed by the present invention, in which the coaxial line type semiconductor structure settles and the coaxial semiconductor light source In the method of manufacturing the coaxial electrode of the present invention, the number of axial electrodes is increased, and the precipitation epitaxy after the Bragg diffraction grating is first fabricated becomes a laser crystal bar, which is cut to the minimum number of times and the minimum amount by the length of the fragment. Complete a linear laser. In this kind of coaxial line type semiconductor precipitation manufacturing method, an upright and vacuum controllable cylindrical dielectric (Dielectric) is coated with a plated semiconductor material (or a Bragg diffraction grating previously fabricated on a metal axis body). The core conductor wire of the period length Λ or the sedimentation tank) or the bare metal core wire is arranged as the cathode, and it is fitted to the outside of the dielectric cylinder, and it moves while rotating up and down. A ring-shaped coil is arranged as an anode to constitute a DC or high-frequency high-pressure plasma emitting device, and the inside of the cylinder is caused by DC or high-frequency plasma discharge (RF Discharge Plasma) between both coaxial electrodes formed inside and outside the dielectric cylinder. It is a precipitation method that provides the energy of passing chemical reaction versus discharge ionization and has reactive ions or epitaxy on the surface of the axial electrode The ring anode moves once at both ends on the outside of the dielectric cylinder, i.e., a deposited thin film layer of a concentric annular semiconductor layer of one layer material that has passed through the chemical vapor phase along the surface of the axial negative electrode line inside the dielectric cylinder. This is shown in FIG. 7A. The thickness of the precipitation epitaxy is controlled by the moving speed, the outflow or flow rate of the reactants, the temperature and pressure, or factors in various processes. The semiconductor of each layer repeatedly has a concentric ring-shaped semiconductor or conductor layer of the respective layers constituting the coaxial line type semiconductor by predetermining the thickness of each material and different types of precipitation in advance. The step-by-step process produces a coaxial semiconductor laser source base bar structure with a long precipitation process. The configuration of this long coaxial line type semiconductor light source base bar is simply referred to as a laser crystal bar (Laser Ingot). Thereafter, the laser crystal bar is taken out of the cylinder, and the ends are divided and polished to form a coaxial laser diode that can be used through a current. This is shown in FIG. 8A. 801 represents a coaxial axial electrode, 802 represents P ⁺ type InP, 801 and 802 form a Bragg grating distributed feedback layer base bar, and 803 represents an Al _{x Galx} As P type annular limiting layer. , 804 represents a P-type active working layer of GaAs, 805 represents an Al _x Ga _lx As material of an N-type limiting layer, 806 represents an outer outer ring feed electrode, 807 represents an insulating reflective layer, 808 Represents a protective reflective layer. FIG. 8B shows a manufacturing flow chart of a coaxial laser diode, 809 shows a Bragg grating base bar manufactured in advance before precipitation, 810 shows a laser crystal bar in which precipitation is completed, and 811 shows a coaxial wire type cut by dividing. A laser crystal bar is represented, and 812 represents a package for completing a power supply base.

The process of this type of coaxial laser diode bar is a process of taking out a Bragg diffraction grating manufactured in advance before precipitation, or taking it out to produce a Bragg diffraction grating during the process, and then placing it again in the cylinder and continuing the precipitation. Including. Since the beam exit of the coaxial laser is not obstructed by the electrode, the coaxial laser generates a laser light having a relatively long and large light emitting active layer volume. Further, the laser crystal bar cuts both the upper and lower surfaces by generating a coaxial laser, and the cut amount is extremely low. The aim is to significantly reduce the consumption of precious semiconductor materials compared to the conventional laser six-sided cut amount, greatly reduce costs, and spread. The VLSED method of “Taiwan patent claim number: 096169661” and the patent name “Solid-state lighting device having a coaxial light-emitting diode structure”, which have been claimed by himself again, have a large amount of vertical and consensus linear epitaxy precipitation (Vertical, Large-number, Synchronizing and Line-Shape Epitaxy Deposition) is utilized as shown in FIG. 7B. This is to produce a coaxial laser crystal bar in a large amount in synchronism, and to simplify the manufacture is a coaxial highlight laser manufacturing method that selects the Bragg diffraction process, as described in Example 1, It is the best technical method to solve the above problem.

2. A coaxial light emitting fiber (Coaxial Lighting Optical Fiber) emits a coaxial laser uniformly and serves the purpose of illumination. Coaxial light-guide optical fibers are manufactured at a radius by a diffractive index distribution and differ from a conventional diffractive index distribution in a diameter fiber. The structure of the diffractive index at the axial center is the same as that from the outside of the coaxial, and the diffractive index distribution moves from the axial center according to the light guide to reach the optical fiber of the radius, and the optical break is transmitted between the axial center and the coaxial outer shell. However, since it does not propagate in the axis, and the axial diffractive index and the outer shell diffractive index are the same, the light wave is propagated in an annular belt-shaped core formed by the middle of each radius from the core transfer arrangement of the concentrated optical fiber axis. This is shown in FIGS. 9A, 9B and 9C. FIG. 9A shows the light in the propagation of the coaxial cage annular core. FIG. 9B is a method of adjusting the self-focusing method of the annular core of the coaxial polymorphic gradient optical fiber. FIG. 9C shows light in the propagation formula of an annular core of a coaxial multi-pattern step rate optical fiber. The incident light waves in the optical fiber are used for transmission of long-distance communication and coaxial light guide fiber.

The present invention has the purpose of illumination in order to uniformly emit a highlight laser at a short distance, and a new coaxial light emitting fiber is produced again. The diffraction index distribution and structure thereof are shown in FIGS. 10A and 10B. As shown in FIG. 10A, the coaxial step rate multi-pattern light-emitting fiber configuration will be described as follows. Reference numeral 1001 is called an annular core layer, and the produced diffraction rate is relatively low. Is represented by n ₁ . 1002 denotes the outer shell (Outcladding), outer殼折Iritsu displays in _o n _2. Reference numeral 1003 denotes an axial clad or an inner clad, and the inner diffractive index is represented by _i n ₂ . The inner and outer diffractive indices are the same, _i n ₂ = _o n ₂ . The 1001 annular core layer has a relatively low refractive index, and 1001 laser light radiated in perfect comparison is emitted out of the optical fiber, which is shown by the lightwave diagram in the optical fiber. The relatively low refractive index annular core layer 1001 includes an inner collar 1003, which has a higher diffraction index than the annular core layer and has a conventional light guide fiber structure. All of the reflected light that has entered the shaft shell cannot be uniformly emitted out of the optical fiber, and the reflection surface 1004 is cut at the end of the coaxial light emitting fiber, so that the light wave in the inner channel is emitted out of the optical fiber. It is necessary to polish the reflecting surface at the end depending on the launch direction so as to have each angle or conical shape. FIG. 10B represents a coaxial single-form step rate luminescent fiber structure.

The present invention utilizes a high-diffractive-index annular core of a light guide in a coaxial fiber structure, changes the annular core structure of a light wave that emits a relatively low diffractive index, and is completely generated by laser light emitted from a coaxial laser semiconductor annular active layer. Emission into the shape core of the coaxial light-emitting fiber in conformity with, and conform to the law of nature. Such as boron, by an annular core to reduce the refractive index impurity materials, fluorine precipitated completed, lower than its diffraction index n ₁ is the inner shells and two diffractive index of the outer shells _i n ₂ and _o n _2. All of the highlight laser light that enters the annular core channel diverges and exits the outside of the optical fiber, and the purpose of illumination is to disperse and uniformly emit laser light waves.

In summary, the above-described two present inventions that provide a method for solving the problem simultaneously solve the above-mentioned drawbacks of the prior art as follows.
First, the coaxial light emitting fiber of the present invention is uniformly distributed and coincides with the highlight laser, which serves a large area illumination purpose. In 1931, the American Lighting Association CIE radiated into the coaxial light-emitting fiber by the three-color wavelength light output from the red, green, and blue coaxial lasers. Achieved that. In addition to the internal wave arrangement of the divergent diffractive index distribution, a synthetic light emitting illumination or LCD backlight structure is manufactured through a set of coaxial light emitting fibers bent and arranged.
2. The method for manufacturing a coaxial laser of the present invention having a coaxial laser diode and a coaxial semiconductor structure is costly due to consumption of laser crystal particles having a limited volume, a limited light emission amount, and a cutting material thereof. Solve the rising problem. The method of producing a precipitation coaxial line laser with a coaxial semiconductor structure produces a laser crystal bar, and the coaxial laser cut already significantly reduces material consumption, thereby significantly reducing costs. Coaxial laser crystal bars that are both vertically and simultaneously manufactured in large quantities are worth saving further, speeding up precipitation many times, and manufacturing in the same process. Also, if it is necessary to produce strong induced luminescence energy, a base diode luminescence structure that produces spontaneous luminescence energy with high efficiency and mass must be constructed. Obviously, the present invention extends the active working layer to increase the amount of initial spontaneous emission photons, converts the lightning energy of the laser expansion action, and as a result has a greater and more effective power output value.

  Since a light emitting diode is a semiconductor element that sends electric energy to light energy, current injection is required, and it is particularly important how the current is uniformly promoted and diffused in the entire light emitting diode. Uniformly enters the active working layer. The electric current that produces the light emission is provided by the axial anode along the axis, and the electric field formed by the voltage provided by the coaxially fed electrodes is created by driving the outer ring conductor (DRIFT) radially and equidistantly by the radius and diffusing and dispersing. Under the driving condition, spontaneous emission (Spontaneous Emission) produced by different light emission operations (Hopping, Exciting ...) is emitted in all directions in holes and electrons in the active layer of circular emission. The two electrodes forming the coaxial power supply flow to the annular light emitting layer between the electrons and holes provided by the two electrodes, travel the shortest distance, and toward the electric field electrode of each radius, that is, the maximum radius. Under the action of the electric field, the carriers move in the electric field driving direction having the maximum radius and become an element for injecting current. By extending the axial electrode of the present invention, the thickness of the concentric semiconductor annular layer manufactured at the center is the same, and all the electrons or holes have a potential barrier configured in the PN uniformly along the shortest path along the radius. , Each of which promotes and diffuses to the outer ring electrode and the axial center electrode, and the combined emission of the light emitting layer after the parallel perforated transmission potential barrier (electron or hole is moved to the dynamic hopping by the polaron Polaron in the organic semiconductor unit. To produce light with an internal quantum efficiency higher than that of a conventional flat layer feeding electric field, thus reducing the production of diffused thermal currents that the conventional light-emitting diodes couple ineffectively, lowering the temperature, and conventional lighting Solves various problems caused by light sources that scatter heat.

  The present invention relates to a coaxial line type laser diode, and is particularly used in lighting applications and solid state light emitting devices and manufacturing methods manufactured by special highlight laser diodes. Examples of the present invention will be described below with examples.

In Example 1, the linear epitaxy precipitation method, which is tuned vertically and in large quantities by the VLSED method shown in FIG. 7B, uses this VLSED method, and a laser crystal having a coaxial linear heterogeneous configuration of 1 meter each in one apparatus. Ten bars can be precipitated at the same time, and the manufactured laser crystal bars are separated and separated to manufacture the coaxial laser diode of FIG. 8B. The manufacturing process starts with an axial base bar (Subrod) 606 of 1 meter and an outer diameter of 2 mm provided in 10 quartz tubes, which is shown in FIG. 7A. The axial center base bar is completed by the VGF crystal method by the vertical stage cooling method shown in FIG. 12A. This axial base bar VGF crystal method includes the following steps:
1. The base of the axial center metal bar 1201 cut by the Bragg diffraction grating is connected to the InP seed 1202 and fixed at the bottom of the crucible 1203.
2. InP polysilicon square material is injected with a crucible.
3. The boiler tube 1206 gradually rises by controlling the curve a according to the temperature level.
4). The boiler tube is regulated by a temperature-controlled curve b, with the lower temperature slowly rising at the 1204 solid-liquid 1205 interface.
5. The initial length of the InP primordial seed solid gradually increases, the liquid area gradually disappears, and grows until it completely covers the entire InP base bar.
6). The InP base bar is taken out and transferred to the coaxial line type laser crystal bar manufactured in the quartz tube of VLSED.

The laser crystal bar is an InP base bar. First, epitaxy, Al _x Ga _lx As P-type annular limiting layer material, then epitaxy GaAs as P-type active working layer, then epitaxy N-type ultimate layer again The Al _{x Gal x} As material and finally the layer that conducts the outer ring feed electrode are deposited again, and at the same time, 10 linear laser crystal bars are completed. This example VLSED-P10 precipitation facility is shown in FIG. 7B, and includes a constant temperature supply tank for various common gas supplies that are instructed and controlled by a computer control system. Among them, the first quartz tube chamber (Reaction Chamber) is an example. In addition, the gas supply method in each branch quartz tube is the same. Reference numeral 20 denotes a constant temperature supply tank for liquid TBAs, which separates the constant temperature incubation and flows to the flow control device 16. When the flow controller 16 is connected to a computer control system to control and output a certain amount, 601 TMGa, 602 TMAI, 603 hydrogen (H ₂ ), or other gases (eg, InGaAs and InP) whose required doping amount is controlled grow. TEAl and TEIn are exchanged or manufactured with a GaInN-based material.) Chemical vapor reactants output by the outflow control system at a constant amount are mixed in the mixer 19, each of which is 10 from the connector. Enter into the quartz tube. For the sake of concise explanation, the frame and the heat insulator to be equipped will not be listed. A linear and cut Bragg diffraction grating having an external diameter of 2 mm has a plated reflective silver layer conductor bar (or InP base bar) inserted into the quartz tube axis. Again, each quartz tube enters with the open-ended chuck 13 and the RF annular pole coil 607 open. Ten parallel-coupled RF power generators 11 are slightly tuned by computer settings and start the epitaxy precipitation process at the same speed as the top and bottom. The pressure inside each quartz tube is controlled by an observation device and a pressure control device 15 under the fixed chuck 14. The exhaust and unprecipitated particles are processed together by a tail exhaust processor 22 through a filter. The joint pump 21 provides the negative pressure condition. Radio frequency plasma discharge (RF DISCHARGE PLASMA) provides the energy of discharge ionization (or PECVD) for chemical reaction pairs in the process of making MOCVD. The high-frequency and high-pressure plasma induction apparatus constituted by each quartz tube axial conductor bar 606 (or InP base bar) grounded to the cathode and the RF annular anode coil 607 on which the quartz tube 1 moves resonates the high-voltage electric field introduced simultaneously. Body, RF annular anode coil 607 flowing in each tube and quartz tube in-core conductor bar 606 provide a gas collapse electric field that exceeds the gas reactant. A high pressure arc lamp is generated between both electrodes. The arc lamp stimulates and emits a large amount of ions and free electrons and activates the annular plasma 608. In the electric field formed by the RF annular anode coil 607 and the in-axis conductor bar 606, electrons are accelerated toward the positive anode and ions are accelerated toward the negative cathode. Due to the small mass of electrons, their acceleration is much greater than that of slowly moving ions. The ions move in the quartz reaction tube, and finally bombard and precipitate the axial center electrode. In this type of impact, if the voltage between the electrodes becomes sufficiently large, the secondary electrons produced by the impact cathode material produce non-elastic impacts of information neutral atoms or molecules, and more ions are produced. The plasma maintains the process of producing ions by emitting electrons twice. At this time, the chemical phase material passing through the inside has already been epitaxially deposited on the axial electrode, and the RF power generator 11 moves the RF annular anode coil 607 to complete the deposition of the concentric annular semiconductor layer 609. Each RF annular anode coil 607 is arranged in parallel with each quartz tube installed vertically along the ground, and moves up and down at the same speed while being tuned. The annular plasma 608 generated in each quartz tube follows the produced precipitate. The semiconductor film thickness or single crystal layer that the linear coaxial light emitting diode constitutes grows. The thickness of the precipitation epitaxy is controlled by the moving speed, the reactant outflow, the flow rate, the temperature and pressure, and various process factors. Repeat one by one, each semiconductor is pre-determined the precipitation of different material thicknesses and types, and finally, 10 coaxial-line laser crystal bars each with a length of 1 meter are completed in one precipitation step. . The taken-out linear laser crystal bar is cut into a required length, and a linear coaxial laser diode is produced in which both ends are protected and fed. This is shown in FIGS. 8A and 8B. The VLSED method of such a Bragg grating base bar is a method of mass-producing a solid linear laser many times, lowering the cost and producing a large number of highlight light sources.

The Bragg diffraction grating cut on the axis conductor of the InP base bar completes its crystal and is taken out, and then the diffraction grating is etched. Alternatively, an InP Bragg grating base bar is manufactured from a Bragg grating crucible in combination, as shown in FIG.

Example 2 is solid state white light illumination in which a coaxial line type laser diode and a coaxial light emitting fiber are combined.

  The combination of the three coaxial line-type red, green, and blue laser diodes and the coaxial white optical fiber manufactured separately in the first embodiment can synthesize a white light solid state lighting device. FIG. 11 is a white light top view in which three cores of white optical fibers of three colors are formed and combined into one. Reference numeral 1101 denotes a red white optical fiber, 1102 denotes a green white optical fiber, 1103 denotes a blue white optical fiber, and 1104 denotes a point irradiated with three-color composite white. One blue coaxial ship laser and one yellow coaxial line laser are separately emitted toward two coaxial light emitting fibers to form a white light solid state lighting device that emits each other.

  Example 3 is a white light illumination device in which a fluorescent powder is formed by blending a coaxial laser diode and a coaxial white optical fiber.

A coaxial line type laser diode is emitted and combined toward a coaxial white optical fiber, and is inserted into a fluorescent tube to form a white light illumination device. This is shown in FIG. 1301 is a blue white optical fiber, 1302 is a second preliminary white optical fiber (a structure for adjusting color development), 1303 is a coating portion in yellow fluorescent powder, and 1304 is an external power supply base of a laser diode having a coaxial line structure. Coaxial line type laser diode is a method that emits light by combining colored fluorescent tube with white coated optical fiber, and it is a light emitting and light emitting technology that fluorescent powder (Phospoor) used by conventional fluorescent lamps produces. This is because there is no need to ionize the gas in the tube and it is not necessary to provide a very high ionization voltage. A conventional light emitting diode LED is formed by adding fluorescent powder to form solid-state lighting. The simplest LED includes one fluorescent powder, and a blue LED is yellow fluorescent powder YAG: Ce (Chemical (Y _1-a Gd _a ) ₃ (Al _1-b Ga _b ) O ₁₂ material) is added to form a blue dielectric YAG: Ce fluorescent powder having a wavelength of 465 nm, and light having a yellow 555 nm optical score is generated. This yellow and LED are not yet blue combined light emission that absorbs, this is blue that is LED absorbed and has no white light combined, which is the simplest, called 1-PCLED (Phosphor Converted LED). The fluorescent powder method of LED stimulated emission increases by 2, 3, 4, 5 or more, so that the fluorescent powder that stimulates and emits different colors in one, two, three, or more LEDs is The purpose is light-emitting lighting. The above-mentioned various combination purposes are all characteristics for adjusting excellent light emission illumination, such as color expression CRI (Color Rendering Index, Ra unit), color temperature CCT (Correlated Color Temperature, K), luminous efficiency (Luminous Efficiency, lm / W) etc. In addition, a fluorescent powder method is added to a purple or ultraviolet UV LED to obtain a light emitting illumination method. This embodiment replaces the coaxial line type LED: adopts two coaxial line type laser diodes again and produces blue coaxial line type laser or one high CRI coaxial line type laser as shown in the example, and two coaxial light emitting fibers This is a method of producing a linear light-emitting lighting device by injecting and then covering the mantle again with a yellow fluorescent powder tube. The present invention has a long linear light emitting layer, produces a long and large light emitting area, emits light more strongly and efficiently with a coaxial laser structure, and replaces a conventional fluorescent lamp.

  Example 4 is a laser pistol. The coaxial line type laser diode is concentrated, and the bundle launch structure produces a solid high energy light source, which is called a laser pistol. FIG. 14 shows a single laser pistol light source of this embodiment. The laser diode 1401 having the coaxial columnar structure is charged in a pipe 1402 for diffusing and protecting heat, and is inserted in a battery and a control circuit base 1403 to complete a laser pistol. This laser pistol alone can be easily produced by collecting and synthesizing 36 coaxial laser bundles so that each external environment electrode has the same potential (negative ground). Each coaxial laser is emitted by 1 watt, and it works in a very small area by concentrating 36 watts. The purpose of power concentration is to define the type using wavelength. In addition, the number of concentrated linear lasers increased greatly, and the power expanded to multiples reached the purpose of use, and the diameter of the coaxial linear laser was extremely small. It is rough and inconvenient for strawberries.

  If a focus adjustment device is mounted in front of the shooting target far enough from the shooting target, or if a laser tuning light control device is produced in which the mechanical structure emits in a straight line, a more reliable highlight or high heat concentration effect is obtained. In addition, the coaxial light source structure can be extended and manufactured, and the linear laser can be manufactured easily, with a small volume and light weight. It is convenient, and can be manufactured as a medical or beauty device by connecting the front end to a coaxial light guide fiber. The operation is convenient, and if a point or surface is ejected to the standard, and if it is manufactured as an industrial or probing function, a weapon with excellent defense power can be deployed. A safety layer is required and the laser pistol part should not be released after 18 months.

  Each embodiment of the present invention has been described in detail with reference to the reference cases, all of which are homologous or functionally similar, and explain the main points shown by the embodiments in an extremely simple illustration system. It is not an actual embodiment shown in this figure, that is, it is not drawn by the element size and number according to the actual drawing, so the drawing shown is not drawn by ratio, and the basics of the coaxial line type lightning diode of the present invention Drawing with the spirit.

  As described above, the illumination device to be manufactured with the coaxial laser diode of the present invention shown in the drawing by way of example not only takes up the structure having the coaxial semiconductor light source of the present invention, but also insists on the common use of the coaxial of the main spirit. Equally shared light emitting function and various applications will be described.

  As described in the examples, various light-emitting solid state lighting devices formed by the present coaxial line type laser diode and coaxial light emitting fiber and the manufacturing method of the coaxial line type laser diode have high luminous efficiency (lm / W), luminous intensity (lm / lamp) and a single process, not only to increase the length of the advanced coaxial laser crystal bar, but also for the lighting products and low-cost mass production in various applications, the coaxial power saving structure saves energy The purpose is to save.

   The above-mentioned function and its coaxial-use light emission function are two or more functions and the method of mass production in synchronism with the coaxial is applied effectively alone or collectively, and in the coaxial common light-emitting system and process system different from the above, It will be useful.

  This text explains the configuration of the white light fixed illumination formed by the coaxial line type laser diode and the coaxial emitting fiber, and explains the present invention in detail. However, the present invention is not limited to these illustrations, and the spirit of the present invention. However, the present invention can be modified and changed in configuration under any premise.

  As described above, all of the gist of the present invention is shown, and it can be applied by a person who has knowledge from the viewpoint of the prior art, and various applications can be applied under the premise of the general specific basic features of the present invention. However, it is easy to modify the present invention, such as applying the present invention with other materials, and these modifications are intended to be included within the meaning and scope of the claims of the present invention.

1 is a schematic diagram of an untuned spontaneous light emitting diode. FIG. Schematic of a tuned stimulated light emitting laser diode. Schematic of heterogeneous configuration light emitting diodes producing a Fabry-Perot laser. The characteristic view of the solid-state semiconductor light emission power with respect to an electric current. 1 is a schematic cross-sectional view of a coaxial semiconductor laser configuration. Schematic of a cross section of a vertical cavity surface type laser light source VCSEL. The schematic of the cross section of a DFB end face type laser diode. Schematic of axial copper electrode starting epitaxy precipitation in a quartz tube using plasma. Schematic of epitaxy precipitation process system for VLSED coaxial laser bar Schematic diagram of coaxial laser diode Manufacturing flow of coaxial line type laser diode Schematic diagram of coaxial fiber 態 step-rate fiber Schematic of multi-pattern gradient fiber of coaxial fiber Schematic of coaxial multi-pattern step rate fiber of coaxial fiber Schematic diagram of multi-pattern light-emitting fiber structure with coaxial step rate Schematic diagram of coaxial single-form step rate light-emitting fiber structure The overhead view of bundle synthetic | combination light emission which consists of a three-color light emission fiber three core. Schematic of the Bragg grating base bar completed by the VGF crystal growth method Schematic of completed Bragg grating axis base bar produced by VGF crystal growth method Schematic diagram of a fluorescent tube device loaded with a coaxial line laser and coaxial light emitting fiber Schematic of laser pistol light source single three-dimensional structure device

Explanation of symbols

11 RF power generator 13 Both-end chuck 14 Fixed chuck 15 Pressure controller 22 Exhaust processor 21 Joint pump 200 Positive voltage supply electrode 201 p-type AlGaAs semiconductor 202 n-type AlGaAs semiconductor 203 n ⁺ -type GaAs substrate 204 p ⁺ -type GaAs substrate 205 Negative Voltage supply electrode 206 Active layer p-type GaAs semiconductor limiting layer or covering layer 403 Bragg distribution feedback layer diffraction grating 404 Annular semiconductor layer 406 Reflective layer 407 Conductor axis electrode 408 Coaxial outer ring feed electrode 409 n-type InP substrate 501 Lower end Bragg reflection Mirror 502 working layer 503 buffer layer 505 upper end Bragg reflection mirror 506 annular electrode 606 quartz tube axial conductor bar 607 RF annular anode coil 608 annular plasma 801 coaxial axial electrode 802 p ⁺ type InP
803 p-type annular limiting layer 804 p-type active working layer 805 n-type limiting layer Al _x Ga _lx As material 806 outer layer outer ring feeding electrode 807 insulating reflective layer 808 protective reflective layer 809 Precipitating Bragg diffraction grating base bar to be formed 810 Precipitating the completed laser crystal bar 811 Dividing the coaxial laser crystal bar 812 Package for completing the power supply pedestal 1001 Ring core layer 1002 Outer shell 1003 Axial shell or inner shell 1101 Red light emitting illumination device 1102 Green light emitting illumination device 1103 Blue Light-emitting lighting device 1104 Point irradiated by three-color composite white 1201 Axial metal bar 1202 InP seed 1203 Crucible 1206 Boiler tube 1301 Blue light-emitting fiber 1302 Second light-emitting fiber 1303 Covered portion 1304 in yellow fluorescent powder Coaxial line type structure Have Laser diode 1402 long pipe 1403 controller pedestal having an external power supply pedestal 1401 coaxial pillar structure of that laser diode

Claims (1)

A laser diode having a coaxial linear structure,
An axial electrode engraved with a predetermined lattice pattern;
An outer ring conductor;
A concentric annular semiconductor layer comprising a plurality of layers installed between the axial electrode and the outer ring conductor and stimulated emission in the axial direction;
The concentric annular semiconductor layer includes a P-type annular semiconductor layer formed outside the axial center electrode, a P-type annular limiting layer formed outside the P-type annular semiconductor layer, and the P-type annular semiconductor layer. A P-type annular active layer formed outside the limiting layer, and an N-type annular limiting layer formed outside the P-type cyclic active layer,
Laser diodes, laser diode having a coaxial line structure, characterized in that it is achieved by the DFB effect of the distributed coaxial annular Bragg gratings distributed along the direction of the axis having the coaxial line structure.